Bonding-Directed Crystallization of Ultra-Long One-Dimensional NbS3 van der Waals Nanowires.

The rediscovery of one-dimensional (1D) and quasi-1D (q-1D) van der Waals (vdW) crystals ushered the realization of nascent physical properties in 1D that are suitable for applications in photonics, electronics, and sensing. However, despite renewed interest in the creation and understanding of the physical properties of 1D and q-1D vdW crystals, the lack of accessible synthetic pathways for growing well-defined nanostructures that extend across several length scales remains. Using the highly anisotropic 1D vdW NbS3-I crystal as a model phase, we present a catalyst-free and bottom-up synthetic approach to access ultralong nanowires, with lengths reaching up to 7.9 mm and with uniform thicknesses ranging from 13 to 160 nm between individual nanowires. Control over the synthetic parameters enabled the modulation of intra- and interchain growth modalities to selectively yield only 1D nanowires or quasi-2D nanoribbons. Comparative synthetic and density functional theory (DFT) studies with a closely related nondimerized phase, ZrS3, show that the unusual preferential growth along 1D can be correlated to the strongly anisotropic bonding and dimeric nature of NbS3-I.

Acute changes in kidney function and outcomes following an acute myocardial infarction: Insights from PARADISE-MI.

AIMS: Pharmacologic blockade of neurohormonal pathways in patients with acute myocardial infarction (MI) can result in acute changes in biomarkers of kidney function. We evaluated the effect of sacubitril/valsartan versus ramipril on initial changes in serum creatinine and the association of these changes with longer-term outcomes among participants in PARADISE-MI. METHODS AND RESULTS: In this randomized, double-blind, active-controlled, event-driven trial, 5661 patients with an acute MI were assigned to receive sacubitril/valsartan or ramipril, with no run-in. The frequency of an initial pre-specified increase in serum creatinine (≥26.5 or ≥44 µmol/L) from baseline to week 1 was compared between arms. Multivariable Cox regression models were fit to examine the association of acute changes in serum creatinine with the primary cardiovascular composite outcome (cardiovascular death, first heart failure hospitalization, or outpatient heart failure), all-cause mortality, and longer-term changes in estimated glomerular filtration rate (eGFR). An initial increase in serum creatinine ≥26.5 µmol/L occurred in 155 of 2604 (6.0%) patients assigned to sacubitril/valsartan and 120 of 2603 (4.6%) patients assigned to ramipril (odds ratio [OR] 1.32; 95% confidence interval [CI] 1.03-1.68). The corresponding numbers for an increase ≥44 µmol/L were 57 (2.2%) and 42 (1.6%), respectively (OR 1.37; 95% CI 0.92-2.05). A higher odds of increased serum creatinine ≥26.5 and ≥44 µmol/L for sacubitril/valsartan versus ramipril appeared to be restricted to patients who had a greater decline in systolic blood pressure over the same period (p-interaction = 0.05 and 0.001, respectively). In multivariable analyses, neither an acute increase in serum creatinine ≥26.5 or ≥44 µmol/L was associated with a higher risk of cardiovascular outcomes, all-cause mortality, or differences in longer-term eGFR slope. Findings were similar across the randomized treatment arms (p-interaction >0.6 for all). CONCLUSIONS: Following acute MI, patients assigned to sacubitril/valsartan had a higher frequency of initial increases in serum creatinine at 1 week, compared with ramipril. In adjusted models, initial increases in serum creatinine with either treatment were not associated with adverse cardiovascular outcomes or changes in longer-term kidney function.

Exceptional electronic transport and quantum oscillations in thin bismuth crystals grown inside van der Waals materials.

Confining materials to two-dimensional forms changes the behaviour of the electrons and enables the creation of new devices. However, most materials are challenging to produce as uniform, thin crystals. Here we present a synthesis approach where thin crystals are grown in a nanoscale mould defined by atomically flat van der Waals (vdW) materials. By heating and compressing bismuth in a vdW mould made of hexagonal boron nitride, we grow ultraflat bismuth crystals less than 10 nm thick. Due to quantum confinement, the bismuth bulk states are gapped, isolating intrinsic Rashba surface states for transport studies. The vdW-moulded bismuth shows exceptional electronic transport, enabling the observation of Shubnikov-de Haas quantum oscillations originating from the (111) surface state Landau levels. By measuring the gate-dependent magnetoresistance, we observe multi-carrier quantum oscillations and Landau level splitting, with features originating from both the top and bottom surfaces. Our vdW mould growth technique establishes a platform for electronic studies and control of bismuth's Rashba surface states and topological boundary modes1-3. Beyond bismuth, the vdW-moulding approach provides a low-cost way to synthesize ultrathin crystals and directly integrate them into a vdW heterostructure.

Therapeutic potential of exosome derived from hepatocyte growth factor-overexpressing adipose mesenchymal stem cells in TGFß1-stimulated hepatic stellate cells.

Cirrhosis is a familiar end-stage of multiple chronic liver diseases. The gene-modified mesenchymal stem cells (MSCs) have become one of the most promising schemes for the treatment of cirrhosis. MSCs exhibit their therapeutic role mainly by secreting hepatocyte growth factor (HGF). The aim of this research was to probe the anti-fibrosis role of exosomes secreted by HGF modified-mouse adipose MSCs (ADMSCs) on activated hepatic stellate cells (HSCs) and to preliminarily explore the possible mechanism. Firstly, mouse ADMSCs were isolated and identified. Quantitative real-time polymerase chain reaction verified the transfection efficiency of ADMSC transfected with HGF lentivirus. Exosomes derived from ADMSC transfecting negative control/HGF (ADMSCNC-Exo/ADMSCHGF-Exo) were extracted by density gradient centrifugation. HSCs were allocated to the control, TGF-ß, TGF-ß + ADMSC-Exo, TGF-ß + ADMSCNC-Exo, and TGF-ß + ADMSCHGF-Exo groups. Moreover, all mice were distributed to the control, CCl4 (40% CCl4 in olive oil), CCl4+ADMSC-Exo, CCl4+ADMSCNC-Exo, and CCl4+ADMSCHGF-Exo groups. Exosomes derived from ADMSCs with or without HGF transfection suppressed HSC activation, as evidenced by attenuating cell viability and cell cycle arrest at S phase but inducing apoptosis. Moreover, ADMSC-Exo, ADMSCNC-Exo, and ADMSCHGF-Exo effectively repressed the gene and protein levels of α-SMA, Col-I, Rho A, Cdc42, and Rac1 in TGF-ß-treated HSCs, and ADMSCHGF-Exo had the best effect. ADMSCHGF-Exo had a stronger regulatory effect on serum liver index than ADMSCNC-Exo in CCl4-induced mice. In conclusion, ADMSCHGF-Exo alleviated liver fibrosis by weakening the Rho pathway, thus reducing collagen production.

Sensitive Thermochromic Behavior of InSeI, a Highly Anisotropic and Tubular 1D van der Waals Crystal.

Thermochromism, the change in color of a material with temperature, is the fundamental basis of optical thermometry. A longstanding challenge in realizing sensitive optical thermometers for widespread use is identifying materials with pronounced thermometric optical performance in the visible range. Herein, it is demonstrated that single crystals of indium selenium iodide (InSeI), a 1D van der Waals (vdW) solid consisting of weakly bound helical chains, exhibit considerable visible range thermochromism. A strong temperature-dependent optical band edge absorption shift ranging from 450 to 530 nm (2.8 to 2.3 eV) over a 380 K temperature range with an experimental (dEg/dT)max value extracted to be 1.26 × 10-3 eV K-1 is shown. This value lies appreciably above most dense conventional semiconductors in the visible range and is comparable to soft lattice solids. The authors further seek to understand the origin of this unusually sensitive thermochromic behavior and find that it arises from strong electron-phonon interactions and anharmonic phonons that significantly broaden band edges and lower the Eg with increasing temperature. The identification of structural signatures resulting in sensitive thermochromism in 1D vdW crystals opens avenues in discovering low-dimensional solids with strong temperature-dependent optical responses across broad spectral windows, dimensionalities, and size regimes.

Controllable strain-driven topological phase transition and dominant surface-state transport in HfTe5.

The fine-tuning of topologically protected states in quantum materials holds great promise for novel electronic devices. However, there are limited methods that allow for the controlled and efficient modulation of the crystal lattice while simultaneously monitoring the changes in the electronic structure within a single sample. Here, we apply significant and controllable strain to high-quality HfTe5 samples and perform electrical transport measurements to reveal the topological phase transition from a weak topological insulator phase to a strong topological insulator phase. After applying high strain to HfTe5 and converting it into a strong topological insulator, we found that the resistivity of the sample increased by 190,500% and that the electronic transport was dominated by the topological surface states at cryogenic temperatures. Our results demonstrate the suitability of HfTe5 as a material for engineering topological properties, with the potential to generalize this approach to study topological phase transitions in van der Waals materials and heterostructures.